diff options
author | Jeff Dike <jdike@addtoit.com> | 2006-06-30 10:55:56 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-30 20:25:37 +0200 |
commit | 572e614750c3ed27da1ec6b75dc486066a11fffd (patch) | |
tree | 50459d715a5145e43c7da1e0d87a85582258ca94 /arch | |
parent | [PATCH] uml: unregister useless console when it's not needed (diff) | |
download | linux-572e614750c3ed27da1ec6b75dc486066a11fffd.tar.xz linux-572e614750c3ed27da1ec6b75dc486066a11fffd.zip |
[PATCH] uml: add locking to xtime accesses
do_timer must be called with xtime_lock held. I'm not sure boot_timer_handler
needs this, however I don't think it hurts: it simply disables irq and takes a
spinlock.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/um/kernel/time_kern.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/um/kernel/time_kern.c b/arch/um/kernel/time_kern.c index 87cdbc560d36..08dd727e79e4 100644 --- a/arch/um/kernel/time_kern.c +++ b/arch/um/kernel/time_kern.c @@ -96,11 +96,15 @@ void time_init_kern(void) void do_boot_timer_handler(struct sigcontext * sc) { + unsigned long flags; struct pt_regs regs; CHOOSE_MODE((void) (UPT_SC(®s.regs) = sc), (void) (regs.regs.skas.is_user = 0)); + + write_seqlock_irqsave(&xtime_lock, flags); do_timer(®s); + write_sequnlock_irqrestore(&xtime_lock, flags); } static DEFINE_SPINLOCK(timer_spinlock); @@ -125,15 +129,17 @@ irqreturn_t um_timer(int irq, void *dev, struct pt_regs *regs) unsigned long long nsecs; unsigned long flags; + write_seqlock_irqsave(&xtime_lock, flags); + do_timer(regs); - write_seqlock_irqsave(&xtime_lock, flags); nsecs = get_time() + local_offset; xtime.tv_sec = nsecs / NSEC_PER_SEC; xtime.tv_nsec = nsecs - xtime.tv_sec * NSEC_PER_SEC; + write_sequnlock_irqrestore(&xtime_lock, flags); - return(IRQ_HANDLED); + return IRQ_HANDLED; } long um_time(int __user *tloc) |